Silent and reduced vibration chainwheel

Abstract

A silent and reduced vibration chainwheel includes a disk, multiple teeth and an energy absorber. The disk has an outer edge, two opposite sides and at least one recess. The teeth are formed radially at and extend out from the outer edge of the disk. The energy absorber is made of resilient material and is mounted in the at least one recess at the outer edge of the disk to absorb the impact of a chain driven by or driving the chainwheel and reduce the noise and vibrations caused by the impact of the chain and the chainwheel. The energy absorber can be resilient annular rings, strips, rods or a combination of them. Therefore, the chainwheel is silent and fewer vibrations are produced so a person who uses a machine that has the chainwheel will feel comfortable.

1. A silent and reduced vibration chainwheel for meshing with a chain, and comprising:
 a disk having an outer edge, two opposite sides and at least one recess; 
 multiple teeth formed with and extending radially out from the outer edge of the disk and forming a bottom land between adjacent teeth and each tooth having a tooth profile with a pitch point; and 
 an energy absorber made of resilient material and mounted at the outer edge of the disk in the at least one recess to absorb shock generated when the chainwheel and the chain contact each other, thereby reducing both vibrations and noise, 
 wherein the teeth are hollow to form a passage in each tooth; 
 the at least one recess in the disk is implemented with a continuous annular groove defined around the outer edge, and extending through and communicating with the passages in the teeth; and 
 the energy absorber comprises a continuous resilient annular strip mounted in the annular groove and extending through the passages in the teeth and around the edge. 
 
   
   
     2. The silent and reduced vibration chainwheel as claimed in  claim 1 , wherein the chainwheel further comprises:
 two side disks smaller than the disk forming the chainwheel, having respectively outer edges and disposed on opposite sides of the disk such that the outer edges of the side disks form two annular shoulders respectively on opposite sides of the chainwheel disk at the teeth; and 
 the at least one recess further comprises the two shoulders, and the energy absorber further comprises two resilient annular rings mounted respectively on the annular shoulders. 
 
   
   
     3. The silent and reduced vibration chainwheel as claimed in  claim 2  wherein the energy absorber comprises multiple, continuous resilient annular strips extending through the passages in the teeth. 
   
   
     4. The silent and reduced vibration chainwheel as claimed in  claim 1 , wherein
 the chainwheel further comprises: 
 two side disks smaller than the disk forming the chainwheel, having respectively outer edges and disposed on opposite sides of the disk such that the outer edges of the side disks form two annular shoulders respectively on opposite sides of the chainwheel disk; 
 the at least one recess is implemented with the two annular shoulders in addition to multiple passages defined respectively in the teeth and a central annular groove defined between the annular shoulders and passing through the teeth; and 
 the energy absorber is implemented with three resilient annular rings mounted respectively on the annular shoulders and in the central annular groove. 
 
   
   
     5. The silent and reduced vibration chainwheel as claimed in  claim 4  wherein the energy absorber comprises multiple, continuous resilient annular strips extending through the passages in the teeth. 
   
   
     6. The silent and reduced vibration chainwheel as claimed in  claim 1  wherein the energy absorber comprises multiple, continuous resilient annular strips extending through the passages in the teeth.